Granted Patent B2

US 8,033,363 · App. 12/456,977 · Granted Oct 11, 2011

Abstract

Claims (7)

1. A method for producing a knee brace rail shield combination for a rail having a web, a first flange and a second flange of a ladder having at least one rung, comprising the steps of:

placing a metal plate into a mold of the knee brace rail shield combination; and

injection molding plastic into the mold to form the knee brace rail shield combination comprising a first portion that has a shape that conforms with an interior cross sectional surface of the rail; and a second portion that extends from the first portion at a first location to the rung to provide structural support to the rung, the second portion having an attachment portion at a second location spaced apart from the first location that is fixed to the rung, the first portion and the second portion being one continuous piece with the metal plate embedded in the first portion, wherein the first portion has a slot, inserting the bottom of the rail into the slot so the first portion fits around the bottom of the rail, forming the slot with a shape that conforms with an interior cross sectional surface of the rail and an exterior cross-sectional surface of the rail, and a rounded bottom, the slot has a cross-sectional shape of essentially a C, the first portion having an outer side that has an inner surface which is essentially flat and conforms with and contacts the rail web's outer surface and the rail first flange's outer surface and the rail second flange's outer surface and forming at least one hole in the outer side, and an inner side that has an inner surface which is essentially flat and conforms with and contacts the rail web's inner surface and forming at least one hole in the inner side which aligns with the at least one hole of the outer side, the metal plate having at least one hole which aligns with the one hole of the inner side and outer side a rivet extending through the one hole of the outer side and the inner side and the metal plate and the rail web to fix the first portion to the rail, forming the first portion has a shoulder bolt hole for a shoulder bolt that holds a safety shoe to the first portion, and forming the first portion with ribs along the bottom of the first portion to absorb forces while the ladder is in use.

2. The method as described in claim 1 wherein the second portion forms an angle of between 5 and 85 degrees with the first portion.

3. The method as described in claim 2 wherein the second portion has a first face which resists twisting that extends from a top edge of the first portion, and a second face extending perpendicularly from the first face along the first face and from the first portion.

4. The method as described in claim 1 wherein the second portion includes a buttress that extends from the second face and the first portion.

5. The method as described in claim 1 wherein the first portion includes a first flange portion attached to and extending from the outer side and the inner side and defining an opening that has an essentially cross-sectional rectangular shape that conforms with the first flange's cross-section and which contacts the first flange's outer surface and inner surface, and a second flange portion attached to and extending from the outer side and the inner side and defining an opening that has an essentially cross-sectional rectangular shape that conforms with the second flange's cross-section and which contacts the second flange's outer surface and inner surface.

Assignments (12)